A filter bank multicarrier (FBMC) technology is a multicarrier modem technology. Compared with an orthogonal frequency division multiplexing (OFDM) technology, the FBMC has lower out-of-band radiation and higher spectral efficiency, and has a good application prospect. A typical implementation solution of the FBMC is using the orthogonal frequency division multiplexing/offset quadrature amplitude modulation (OQAM) technology. In an OFDM system, a quadrature amplitude modulation (QAM) symbol of a complex number is sent, and in OFDM/OQAM, an OQAM symbol of a pure real number or a pure imaginary number is sent. Quadrature of transmit signals in a frequency domain and a time domain is implemented by using a quadrature characteristic of a prototype filter in a real number domain.
In an FBMC system, a transmit end and a receive end respectively implement FBMC modulation and demodulation of frequency domain data and received time domain data of a user by using respective poly-phase network (PPN) filter banks. The poly-phase network filter bank of the transmit end is referred to as a synthesis filter bank (SFB). The poly-phase network filter bank of the receive end is referred to as an analysis filter bank (AFB).
However, as a multicarrier technical solution, the FBMC has a relatively high peak-to-average ratio (PAPR). A high PAPR may cause occurrence of signal distortion and an out-of-band leakage increase after a signal passes through a non-linear radio frequency component, and may also cause an energy efficiency decrease of a power amplifier.
A low-PAPR single carrier signal processing method in the conventional art is: performing AFB filtering on a single carrier signal at a transmit end, and performing SFB filtering after subcarrier mapping and a necessary signal processing process. Because the AFB and the SFB have reciprocity, a signal obtained after the foregoing transform reserves some features of the single carrier signal, and has a relatively low PAPR. The receive end restores a signal by using an inverse process of the transmit end. However, processing methods of AFB filtering and SFB filtering in the processing method has relatively high complexity.